Paper feeding method for printer

ABSTRACT

A paper feeding method for a printer is provided. The method includes the steps of: feeding a paper for printing a first side of the paper; lifting an up-feeding cap and feeding the paper to a place between the up-feeding cap and a feed roller when the first side of the paper is finished printing; laying down the up-feeding cap after a predetermined duration; and reversing the paper for printing the other side of the paper. The method is suitable for two-side printing and capable of avoiding paper jam or paper damage due to paper distortion by ink.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan application serial no. 97121255, filed on Jun. 6, 2008. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of specification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a paper feeding method for a printer, in particular, to a paper feeding method suitable for two-side printing.

2. Description of Related Art

Due to their increasingly reduced prices and high-quality printing effects, laser printers and inkjet printers gradually become indispensable individual or household electronic products. Particularly, when applied to photo printing, the printers may achieve an effect equal to professional photo printing shops, so that personal photos and images of colourful/black and white files become more vivid. Further, via an interface with a high transmission rate (for example, a USB transmission interface), the transmission speed of the printer in a large-sized and high-resolution printing can be accelerated, thus facilitating the printing of high-quality photos for the user.

However, when a two-side printing is performed under a full-page printing mode (generally adapted for photo printing), it is easy to generate a white-edge on the borders of the paper (i.e., unprinted blank areas on the edges of a file). As such, the original image cannot be completely printed on the paper, and the photo quality is affected. Therefore, an over printing technique is put forward, for expanding the print range to exceed the borders of the paper, so as to eliminate the white-edge. However, when a two-side printing is performed under the full-page printing mode, paper jam or paper damage may be caused by paper distortion due to paper wet by ink.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a paper feeding method for a printer. During a two-side printing, a paper is immediately fed by a paper feeding device to a place between a lifted up-feeding cap and a feed roller when a first side of the paper is finished printing. Thereby, the circumstance that the paper may not be successfully fed into a two-side printing module due to paper distortion or the paper may be damaged by an ink absorption fillister can be avoided.

A paper feeding method for a printer adapted for performing a two-side printing on a paper is provided. The method includes the steps of: feeding the paper for printing a first side of the paper; lifting an up-feeding cap and feeding the paper to a place between the up-feeding cap and a feed roller when the first side of the paper is finished printing; laying down the up-feeding cap after a predetermined duration; and reversing the paper for printing a second side of the paper.

In an embodiment of the present invention, the step of feeding the paper for printing the first side of the paper further includes performing a full-page printing and an over printing on the paper.

In an embodiment of the present invention, the step of lifting the up-feeding cap and feeding the paper to a place between the up-feeding cap and the feed roller when the first side of the paper is finished printing further includes feeding the paper to a place between a pitch roller of the up-feeding cap and the feed roller.

In an embodiment of the present invention, the step of lifting the up-feeding cap and feeding the paper to a place between the up-feeding cap and the feed roller when the first side of the paper is finished printing further includes feeding an end portion of the paper to a place between the up-feeding cap and the feed roller.

In an embodiment of the present invention, the step of reversing the paper for printing the second side of the paper further includes feeding the paper into a two-side printing module for reversing the paper, and again feeding the paper for printing the second side of the paper.

In an embodiment of the present invention, a paper feeding method for a printer capable of performing a two-side full-page printing is adapted for performing a two-side full-page printing on a paper. The method includes the steps of: feeding the paper for performing an full-page over printing on a first side of the paper; lifting an up-feeding cap and feeding the paper to a place between the up-feeding cap and a feed roller when the first side of the paper is finished printing; laying down the up-feeding cap after a predetermined duration; and reversing the paper for performing the full-page over printing on a second side of the paper.

In the present invention, the paper with the first side printed is fed in advance to a place between the lifted up-feeding cap and the feed roller, thus avoiding paper jam or paper damage caused by paper distortion due to paper wet by ink.

In order to make the aforementioned features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

FIG. 1 is a partial structural view of a printer according to an embodiment of the present invention.

FIGS. 2( a) to 2(c) are schematic views illustrating the operation of a part of a printer according to an embodiment of the present invention.

FIG. 3 is a flow chart of a paper feeding method for a printer according to an embodiment of the present invention.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.

When a two-side printing is performed under a full-page printing mode, the paper needs to be reversed and then fed again for printing the second side. Having the first side printed, especially in an inkjet printer, the paper may be distorted, for example, curled, when wet by the ink. As a result, when the paper is fed into a two-side printing module for printing the second side, paper jam or paper damage may easily occur. Particularly, during an over printing, the paper with an edge, especially an end portion thereof, curled or distorted may not be successfully fed into the two-side printing module or other paper guiding devices. The paper may also be caught in edges of an ink absorption fillister, and is thus damaged.

Therefore, in this embodiment, a manner of feeding in advance is adopted. When the first side of the paper is finished printing (i.e., the final brushing is finished), the up-feeding cap is immediately lifted, and the end portion of the paper is brought (fed) to a place between the up-feeding cap and the feed roller. After the ink is dried (different durations are predetermined depending on varied types of paper and printer), the up-feeding cap is laid down for feeding the paper into the two-side printing module, so as to reverse and guide the paper. Then, the paper is again fed into the printing area to have the second side printed. In this manner, the paper jam can be avoided, and the effect of shaping the paper is also achieved.

FIG. 1 is a partial structural view of a printer according to an embodiment of the present invention. Referring to FIG. 1, the printer 100 includes a paper tray 110, a printing platform 120, a feed roller 130, an up-feeding cap 140, a printing device 150, and a two-side printing module 160. The printing platform 120 further includes a starting roller 122, and the printing device 150 includes an ink jet printhead (not shown).

The paper is fed into the printing platform 120 through a paper feeding device 112 in the paper tray 110 and the feed roller 130, and then printed in a printing area 170. In addition, the paper feeding paths may refer to paths P1 and P2 in dashed lines. When the first side (front side) of the paper is finished printing in the printing area 170, i.e., the final brushing at the end of the page is finished, the up-feeding cap 140 is immediately lifted, and then the paper is fed to a place between the up-feeding cap 140 and the feed roller 130. After a predetermined duration, the up-feeding cap 140 is laid down by the printer 100, such that the paper is fed into the two-side printing module 160 for being reversed and guided. Then, the paper is again fed into the printing area 170 to have the second side (back side) printed. In addition, the paper transmission paths may refer to paths P3 and P4 in real lines.

It should be noted that, the predetermined duration is set for drying the ink, and the length of the duration varies upon the types of paper, printer, or frame.

Next, the manner of guiding the paper in the printer is further described. FIGS. 2( a) to 2(c) are schematic views illustrating the operation of a part of the printer according to this embodiment. Referring to FIGS. 2( a) to 2(c), mainly the structures around the printing area 170 in FIG. 1 are shown, and the technical means of this embodiment is further described with the paper guiding process.

First, referring to FIG. 2( a), a paper 210 is fed to a place beneath the printing device 150 for printing, and the end portion of the paper 210 will pause at an ink absorption fillister 225 for over printing. When a first side of the paper 210 is finished printing, the up-feeding cap 140 is automatically lifted to form a large space between the up-feeding cap 140 and the feed roller 130, so as to smoothly bring the paper 210 to a place between the up-feeding cap 140 and the feed roller 130. It should be noted that, it only needs to bring the end portion of the paper 210 to a place between the up-feeding cap 140 and feed roller 130, i.e., only the end portion of the paper 210 has to be guided to a place between a pitch roller 145 of the up-feeding cap 140 and the feed roller 130. Referring to FIG. 2( b), the end portion of the paper 210 is brought to a place between the up-feeding cap 140 and the feed roller 130, and meanwhile, the up-feeding cap 140 remains lifted.

When the up-feeding cap 140 is laid down, a part of the paper 210 is located between the pitch roller 145 of the up-feeding cap 140 and the feed roller 130. Thus, no matter being distorted or not, the paper 210 can be successfully fed into the two-side printing module 160 at the rear end without causing paper jam or paper damage. Referring to FIG. 2( c), the paper 210 is sandwiched between the up-feeding cap 140 and the feed roller 130. In this manner, the paper 210 can be prevented from being caught before entering the up-feeding cap 140 and the feed roller 130, or being distorted or damaged by the ink absorption fillister 215, and meanwhile the paper 210 can be fixed.

In addition, it should be noted that, the lifting of the up-feeding cap 140 is not limited to the occasion when the first side of the paper 210 is finished printing, and the up-feeding cap 140 may be lifted as long as the paper 210 leaves the up-feeding cap 140 and the feed roller 130. The reason is that the lifting of the up-feeding cap 140 at this time may not affect the normal feeding operation of the paper 210. In other words, the up-feeding cap 140 only needs to remain lifted after the first side of the paper 210 is finished printing.

Accordingly, in this embodiment, a paper feeding method for a printer adapted for performing a two-side printing is concluded as shown in FIGS. 1, 2(a) to 2(c), and 3. In addition, FIG. 3 is a flow chart of the paper feeding method for a printer according to this embodiment.

The above paper feeding method includes the steps of: feeding the paper for printing a first side of the paper (Step S310); lifting an up-feeding cap and feeding the paper to a place between the up-feeding cap and a feed roller when the first side of the paper is finished printing (Step S320); laying down the up-feeding cap after a predetermined duration (Step S330); and reversing the paper for printing a second side of the paper (Step S340).

In Step S310, a full-page printing and an over printing are further performed on the paper. In Step S320, an end portion of the paper is further fed to a place between the pitch roller of the up-feeding cap and the feed roller. Other implementation details of the paper feeding method can be obtained by referring to FIGS. 1 and 2, and can be easily figured out by those of ordinary skill in the art through the disclosure of the present invention, so the details will not be repeated herein again.

Further, it should be noted that the two-side printing module 160 is mainly adopted to guide and reverse the paper so as to have the second side of the paper printed, and the structure thereof is not limited to this embodiment. The up-feeding cap and the feed roller form the paper feeding device where the paper is fed after the first side is finished printing, and the structure thereof is not limited to the embodiment in FIG. 1. The technical means of the present invention can be adopted to solve any problem related to the circumstance that the paper is distorted after the printing is finished. That is, the paper receiving space of the paper feeding device is enlarged, then the paper is brought to a place between the upper and the lower roller, and the paper feeding operation is performed after the ink is dried. In this manner, paper jam or paper damage caused by paper distortion can be avoided.

In view of the above, the method provided by the present invention is applicable to the paper feeding process during a two-side printing, especially in an inkjet printer. According to the present invention, after the first side of the paper is finished printing, the up-feeding cap is immediately lifted, the paper is then fed to a place between the up-feeding cap and the feed roller, and the operation continues when the ink is dried. In this manner, the circumstance that the paper may not be successfully fed into a two-side printing module due to paper distortion or the paper may be damaged by the ink absorption fillister can be avoided.

It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. 

1. A paper feeding method for a printer, adapted for performing a two-side printing on a paper, the method comprising: feeding the paper for printing a first side of the paper; lifting an up-feeding cap and feeding the paper to a place between the up-feeding cap and a feed roller when the first side of the paper is finished printing; laying down the up-feeding cap after a predetermined duration; and reversing the paper for printing a second side of the paper.
 2. The paper feeding method according to claim 1, wherein the step of feeding the paper for printing the first side of the paper further comprises: performing a full-page printing on the paper.
 3. The paper feeding method according to claim 1, wherein the step of feeding the paper for printing a first side of the paper further comprises: performing an over printing on the paper.
 4. The paper feeding method according to claim 1, wherein the step of lifting the up-feeding cap and feeding the paper to a place between the up-feeding cap and the feed roller when the first side of the paper is finished printing further comprises: feeding the paper to a place between a pitch roller of the up-feeding cap and the feed roller.
 5. The paper feeding method according to claim 1, wherein the step of lifting the up-feeding cap and feeding the paper to a place between the up-feeding cap and the feed roller when the first side of the paper is finished printing further comprises: feeding an end portion of the paper to a place between the up-feeding cap and the feed roller.
 6. The paper feeding method according to claim 1, wherein the step of reversing the paper for printing the second side of the paper further comprises: feeding the paper into a two-side printing module for reversing the paper, and again feeding the paper for printing the second side of the paper.
 7. A paper feeding method for a printer capable of performing a two-side full-page printing, adapted for performing a two-side full-page printing on a paper, the method comprising: feeding the paper for performing an full-page over printing on a first side of the paper; lifting an up-feeding cap and feeding the paper to a place between the up-feeding cap and a feed roller when the first side of the paper is finished printing; laying down the up-feeding cap after a predetermined duration; and reversing the paper for performing the full-page over printing on a second side of the paper. 